Pileus Git - ~andy/linux/blob - drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 /* Uncomment next line to get verbose printout */
  30 /* #define DEBUG */
  31 #define pr_fmt(fmt) "ACPI : EC: " fmt
  32
  33 #include <linux/kernel.h>
  34 #include <linux/module.h>
  35 #include <linux/init.h>
  36 #include <linux/types.h>
  37 #include <linux/delay.h>
  38 #include <linux/interrupt.h>
  39 #include <linux/list.h>
  40 #include <linux/spinlock.h>
  41 #include <linux/slab.h>
  42 #include <linux/acpi.h>
  43 #include <linux/dmi.h>
  44 #include <asm/io.h>
  45
  46 #include "internal.h"
  47
  48 #define ACPI_EC_CLASS                   "embedded_controller"
  49 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  50 #define ACPI_EC_FILE_INFO               "info"
  51
  52 /* EC status register */
  53 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  54 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  55 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  56 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  57
  58 /* EC commands */
  59 enum ec_command {
  60         ACPI_EC_COMMAND_READ = 0x80,
  61         ACPI_EC_COMMAND_WRITE = 0x81,
  62         ACPI_EC_BURST_ENABLE = 0x82,
  63         ACPI_EC_BURST_DISABLE = 0x83,
  64         ACPI_EC_COMMAND_QUERY = 0x84,
  65 };
  66
  67 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  68 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  69 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  70
  71 enum {
  72         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  73         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  74         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  75                                          * OpReg are installed */
  76         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  77 };
  78
  79 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  80 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  81 module_param(ec_delay, uint, 0644);
  82 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  83
  84 /*
  85  * If the number of false interrupts per one transaction exceeds
  86  * this threshold, will think there is a GPE storm happened and
  87  * will disable the GPE for normal transaction.
  88  */
  89 static unsigned int ec_storm_threshold  __read_mostly = 8;
  90 module_param(ec_storm_threshold, uint, 0644);
  91 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
  92
  93 struct acpi_ec_query_handler {
  94         struct list_head node;
  95         acpi_ec_query_func func;
  96         acpi_handle handle;
  97         void *data;
  98         u8 query_bit;
  99 };
 100
 101 struct transaction {
 102         const u8 *wdata;
 103         u8 *rdata;
 104         unsigned short irq_count;
 105         u8 command;
 106         u8 wi;
 107         u8 ri;
 108         u8 wlen;
 109         u8 rlen;
 110         bool done;
 111 };
 112
 113 struct acpi_ec *boot_ec, *first_ec;
 114 EXPORT_SYMBOL(first_ec);
 115
 116 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 117 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 118 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 119
 120 /* --------------------------------------------------------------------------
 121                              Transaction Management
 122    -------------------------------------------------------------------------- */
 123
 124 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 125 {
 126         u8 x = inb(ec->command_addr);
 127         pr_debug("---> status = 0x%2.2x\n", x);
 128         return x;
 129 }
 130
 131 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 132 {
 133         u8 x = inb(ec->data_addr);
 134         pr_debug("---> data = 0x%2.2x\n", x);
 135         return x;
 136 }
 137
 138 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 139 {
 140         pr_debug("<--- command = 0x%2.2x\n", command);
 141         outb(command, ec->command_addr);
 142 }
 143
 144 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 145 {
 146         pr_debug("<--- data = 0x%2.2x\n", data);
 147         outb(data, ec->data_addr);
 148 }
 149
 150 static int ec_transaction_done(struct acpi_ec *ec)
 151 {
 152         unsigned long flags;
 153         int ret = 0;
 154         spin_lock_irqsave(&ec->lock, flags);
 155         if (!ec->curr || ec->curr->done)
 156                 ret = 1;
 157         spin_unlock_irqrestore(&ec->lock, flags);
 158         return ret;
 159 }
 160
 161 static void start_transaction(struct acpi_ec *ec)
 162 {
 163         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 164         ec->curr->done = false;
 165         acpi_ec_write_cmd(ec, ec->curr->command);
 166 }
 167
 168 static void advance_transaction(struct acpi_ec *ec, u8 status)
 169 {
 170         unsigned long flags;
 171         struct transaction *t;
 172
 173         spin_lock_irqsave(&ec->lock, flags);
 174         t = ec->curr;
 175         if (!t)
 176                 goto unlock;
 177         if (t->wlen > t->wi) {
 178                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 179                         acpi_ec_write_data(ec,
 180                                 t->wdata[t->wi++]);
 181                 else
 182                         goto err;
 183         } else if (t->rlen > t->ri) {
 184                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 185                         t->rdata[t->ri++] = acpi_ec_read_data(ec);
 186                         if (t->rlen == t->ri)
 187                                 t->done = true;
 188                 } else
 189                         goto err;
 190         } else if (t->wlen == t->wi &&
 191                    (status & ACPI_EC_FLAG_IBF) == 0)
 192                 t->done = true;
 193         goto unlock;
 194 err:
 195         /*
 196          * If SCI bit is set, then don't think it's a false IRQ
 197          * otherwise will take a not handled IRQ as a false one.
 198          */
 199         if (in_interrupt() && !(status & ACPI_EC_FLAG_SCI))
 200                 ++t->irq_count;
 201
 202 unlock:
 203         spin_unlock_irqrestore(&ec->lock, flags);
 204 }
 205
 206 static int acpi_ec_sync_query(struct acpi_ec *ec);
 207
 208 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 209 {
 210         if (state & ACPI_EC_FLAG_SCI) {
 211                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 212                         return acpi_ec_sync_query(ec);
 213         }
 214         return 0;
 215 }
 216
 217 static int ec_poll(struct acpi_ec *ec)
 218 {
 219         unsigned long flags;
 220         int repeat = 5; /* number of command restarts */
 221         while (repeat--) {
 222                 unsigned long delay = jiffies +
 223                         msecs_to_jiffies(ec_delay);
 224                 do {
 225                         /* don't sleep with disabled interrupts */
 226                         if (EC_FLAGS_MSI || irqs_disabled()) {
 227                                 udelay(ACPI_EC_MSI_UDELAY);
 228                                 if (ec_transaction_done(ec))
 229                                         return 0;
 230                         } else {
 231                                 if (wait_event_timeout(ec->wait,
 232                                                 ec_transaction_done(ec),
 233                                                 msecs_to_jiffies(1)))
 234                                         return 0;
 235                         }
 236                         advance_transaction(ec, acpi_ec_read_status(ec));
 237                 } while (time_before(jiffies, delay));
 238                 pr_debug("controller reset, restart transaction\n");
 239                 spin_lock_irqsave(&ec->lock, flags);
 240                 start_transaction(ec);
 241                 spin_unlock_irqrestore(&ec->lock, flags);
 242         }
 243         return -ETIME;
 244 }
 245
 246 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 247                                         struct transaction *t)
 248 {
 249         unsigned long tmp;
 250         int ret = 0;
 251         if (EC_FLAGS_MSI)
 252                 udelay(ACPI_EC_MSI_UDELAY);
 253         /* start transaction */
 254         spin_lock_irqsave(&ec->lock, tmp);
 255         /* following two actions should be kept atomic */
 256         ec->curr = t;
 257         start_transaction(ec);
 258         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 259                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 260         spin_unlock_irqrestore(&ec->lock, tmp);
 261         ret = ec_poll(ec);
 262         spin_lock_irqsave(&ec->lock, tmp);
 263         ec->curr = NULL;
 264         spin_unlock_irqrestore(&ec->lock, tmp);
 265         return ret;
 266 }
 267
 268 static int ec_check_ibf0(struct acpi_ec *ec)
 269 {
 270         u8 status = acpi_ec_read_status(ec);
 271         return (status & ACPI_EC_FLAG_IBF) == 0;
 272 }
 273
 274 static int ec_wait_ibf0(struct acpi_ec *ec)
 275 {
 276         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 277         /* interrupt wait manually if GPE mode is not active */
 278         while (time_before(jiffies, delay))
 279                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 280                                         msecs_to_jiffies(1)))
 281                         return 0;
 282         return -ETIME;
 283 }
 284
 285 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 286 {
 287         int status;
 288         u32 glk;
 289         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 290                 return -EINVAL;
 291         if (t->rdata)
 292                 memset(t->rdata, 0, t->rlen);
 293         mutex_lock(&ec->mutex);
 294         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 295                 status = -EINVAL;
 296                 goto unlock;
 297         }
 298         if (ec->global_lock) {
 299                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 300                 if (ACPI_FAILURE(status)) {
 301                         status = -ENODEV;
 302                         goto unlock;
 303                 }
 304         }
 305         if (ec_wait_ibf0(ec)) {
 306                 pr_err("input buffer is not empty, "
 307                                 "aborting transaction\n");
 308                 status = -ETIME;
 309                 goto end;
 310         }
 311         pr_debug("transaction start (cmd=0x%02x, addr=0x%02x)\n",
 312                         t->command, t->wdata ? t->wdata[0] : 0);
 313         /* disable GPE during transaction if storm is detected */
 314         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 315                 /* It has to be disabled, so that it doesn't trigger. */
 316                 acpi_disable_gpe(NULL, ec->gpe);
 317         }
 318
 319         status = acpi_ec_transaction_unlocked(ec, t);
 320
 321         /* check if we received SCI during transaction */
 322         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 323         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 324                 msleep(1);
 325                 /* It is safe to enable the GPE outside of the transaction. */
 326                 acpi_enable_gpe(NULL, ec->gpe);
 327         } else if (t->irq_count > ec_storm_threshold) {
 328                 pr_info("GPE storm detected(%d GPEs), "
 329                         "transactions will use polling mode\n",
 330                         t->irq_count);
 331                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 332         }
 333         pr_debug("transaction end\n");
 334 end:
 335         if (ec->global_lock)
 336                 acpi_release_global_lock(glk);
 337 unlock:
 338         mutex_unlock(&ec->mutex);
 339         return status;
 340 }
 341
 342 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 343 {
 344         u8 d;
 345         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 346                                 .wdata = NULL, .rdata = &d,
 347                                 .wlen = 0, .rlen = 1};
 348
 349         return acpi_ec_transaction(ec, &t);
 350 }
 351
 352 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 353 {
 354         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 355                                 .wdata = NULL, .rdata = NULL,
 356                                 .wlen = 0, .rlen = 0};
 357
 358         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 359                                 acpi_ec_transaction(ec, &t) : 0;
 360 }
 361
 362 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 363 {
 364         int result;
 365         u8 d;
 366         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 367                                 .wdata = &address, .rdata = &d,
 368                                 .wlen = 1, .rlen = 1};
 369
 370         result = acpi_ec_transaction(ec, &t);
 371         *data = d;
 372         return result;
 373 }
 374
 375 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 376 {
 377         u8 wdata[2] = { address, data };
 378         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 379                                 .wdata = wdata, .rdata = NULL,
 380                                 .wlen = 2, .rlen = 0};
 381
 382         return acpi_ec_transaction(ec, &t);
 383 }
 384
 385 int ec_read(u8 addr, u8 *val)
 386 {
 387         int err;
 388         u8 temp_data;
 389
 390         if (!first_ec)
 391                 return -ENODEV;
 392
 393         err = acpi_ec_read(first_ec, addr, &temp_data);
 394
 395         if (!err) {
 396                 *val = temp_data;
 397                 return 0;
 398         } else
 399                 return err;
 400 }
 401
 402 EXPORT_SYMBOL(ec_read);
 403
 404 int ec_write(u8 addr, u8 val)
 405 {
 406         int err;
 407
 408         if (!first_ec)
 409                 return -ENODEV;
 410
 411         err = acpi_ec_write(first_ec, addr, val);
 412
 413         return err;
 414 }
 415
 416 EXPORT_SYMBOL(ec_write);
 417
 418 int ec_transaction(u8 command,
 419                    const u8 * wdata, unsigned wdata_len,
 420                    u8 * rdata, unsigned rdata_len)
 421 {
 422         struct transaction t = {.command = command,
 423                                 .wdata = wdata, .rdata = rdata,
 424                                 .wlen = wdata_len, .rlen = rdata_len};
 425         if (!first_ec)
 426                 return -ENODEV;
 427
 428         return acpi_ec_transaction(first_ec, &t);
 429 }
 430
 431 EXPORT_SYMBOL(ec_transaction);
 432
 433 /* Get the handle to the EC device */
 434 acpi_handle ec_get_handle(void)
 435 {
 436         if (!first_ec)
 437                 return NULL;
 438         return first_ec->handle;
 439 }
 440
 441 EXPORT_SYMBOL(ec_get_handle);
 442
 443 void acpi_ec_block_transactions(void)
 444 {
 445         struct acpi_ec *ec = first_ec;
 446
 447         if (!ec)
 448                 return;
 449
 450         mutex_lock(&ec->mutex);
 451         /* Prevent transactions from being carried out */
 452         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 453         mutex_unlock(&ec->mutex);
 454 }
 455
 456 void acpi_ec_unblock_transactions(void)
 457 {
 458         struct acpi_ec *ec = first_ec;
 459
 460         if (!ec)
 461                 return;
 462
 463         mutex_lock(&ec->mutex);
 464         /* Allow transactions to be carried out again */
 465         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 466         mutex_unlock(&ec->mutex);
 467 }
 468
 469 void acpi_ec_unblock_transactions_early(void)
 470 {
 471         /*
 472          * Allow transactions to happen again (this function is called from
 473          * atomic context during wakeup, so we don't need to acquire the mutex).
 474          */
 475         if (first_ec)
 476                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 477 }
 478
 479 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 480 {
 481         int result;
 482         u8 d;
 483         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 484                                 .wdata = NULL, .rdata = &d,
 485                                 .wlen = 0, .rlen = 1};
 486         if (!ec || !data)
 487                 return -EINVAL;
 488         /*
 489          * Query the EC to find out which _Qxx method we need to evaluate.
 490          * Note that successful completion of the query causes the ACPI_EC_SCI
 491          * bit to be cleared (and thus clearing the interrupt source).
 492          */
 493         result = acpi_ec_transaction_unlocked(ec, &t);
 494         if (result)
 495                 return result;
 496         if (!d)
 497                 return -ENODATA;
 498         *data = d;
 499         return 0;
 500 }
 501
 502 /* --------------------------------------------------------------------------
 503                                 Event Management
 504    -------------------------------------------------------------------------- */
 505 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 506                               acpi_handle handle, acpi_ec_query_func func,
 507                               void *data)
 508 {
 509         struct acpi_ec_query_handler *handler =
 510             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 511         if (!handler)
 512                 return -ENOMEM;
 513
 514         handler->query_bit = query_bit;
 515         handler->handle = handle;
 516         handler->func = func;
 517         handler->data = data;
 518         mutex_lock(&ec->mutex);
 519         list_add(&handler->node, &ec->list);
 520         mutex_unlock(&ec->mutex);
 521         return 0;
 522 }
 523
 524 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 525
 526 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 527 {
 528         struct acpi_ec_query_handler *handler, *tmp;
 529         mutex_lock(&ec->mutex);
 530         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 531                 if (query_bit == handler->query_bit) {
 532                         list_del(&handler->node);
 533                         kfree(handler);
 534                 }
 535         }
 536         mutex_unlock(&ec->mutex);
 537 }
 538
 539 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 540
 541 static void acpi_ec_run(void *cxt)
 542 {
 543         struct acpi_ec_query_handler *handler = cxt;
 544         if (!handler)
 545                 return;
 546         pr_debug("start query execution\n");
 547         if (handler->func)
 548                 handler->func(handler->data);
 549         else if (handler->handle)
 550                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 551         pr_debug("stop query execution\n");
 552         kfree(handler);
 553 }
 554
 555 static int acpi_ec_sync_query(struct acpi_ec *ec)
 556 {
 557         u8 value = 0;
 558         int status;
 559         struct acpi_ec_query_handler *handler, *copy;
 560         if ((status = acpi_ec_query_unlocked(ec, &value)))
 561                 return status;
 562         list_for_each_entry(handler, &ec->list, node) {
 563                 if (value == handler->query_bit) {
 564                         /* have custom handler for this bit */
 565                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 566                         if (!copy)
 567                                 return -ENOMEM;
 568                         memcpy(copy, handler, sizeof(*copy));
 569                         pr_debug("push query execution (0x%2x) on queue\n",
 570                                 value);
 571                         return acpi_os_execute((copy->func) ?
 572                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 573                                 acpi_ec_run, copy);
 574                 }
 575         }
 576         return 0;
 577 }
 578
 579 static void acpi_ec_gpe_query(void *ec_cxt)
 580 {
 581         struct acpi_ec *ec = ec_cxt;
 582         if (!ec)
 583                 return;
 584         mutex_lock(&ec->mutex);
 585         acpi_ec_sync_query(ec);
 586         mutex_unlock(&ec->mutex);
 587 }
 588
 589 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 590 {
 591         if (state & ACPI_EC_FLAG_SCI) {
 592                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 593                         pr_debug("push gpe query to the queue\n");
 594                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 595                                 acpi_ec_gpe_query, ec);
 596                 }
 597         }
 598         return 0;
 599 }
 600
 601 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 602         u32 gpe_number, void *data)
 603 {
 604         struct acpi_ec *ec = data;
 605         u8 status = acpi_ec_read_status(ec);
 606
 607         pr_debug("~~~> interrupt, status:0x%02x\n", status);
 608
 609         advance_transaction(ec, status);
 610         if (ec_transaction_done(ec) &&
 611             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 612                 wake_up(&ec->wait);
 613                 ec_check_sci(ec, acpi_ec_read_status(ec));
 614         }
 615         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 616 }
 617
 618 /* --------------------------------------------------------------------------
 619                              Address Space Management
 620    -------------------------------------------------------------------------- */
 621
 622 static acpi_status
 623 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 624                       u32 bits, u64 *value64,
 625                       void *handler_context, void *region_context)
 626 {
 627         struct acpi_ec *ec = handler_context;
 628         int result = 0, i, bytes = bits / 8;
 629         u8 *value = (u8 *)value64;
 630
 631         if ((address > 0xFF) || !value || !handler_context)
 632                 return AE_BAD_PARAMETER;
 633
 634         if (function != ACPI_READ && function != ACPI_WRITE)
 635                 return AE_BAD_PARAMETER;
 636
 637         if (EC_FLAGS_MSI || bits > 8)
 638                 acpi_ec_burst_enable(ec);
 639
 640         for (i = 0; i < bytes; ++i, ++address, ++value)
 641                 result = (function == ACPI_READ) ?
 642                         acpi_ec_read(ec, address, value) :
 643                         acpi_ec_write(ec, address, *value);
 644
 645         if (EC_FLAGS_MSI || bits > 8)
 646                 acpi_ec_burst_disable(ec);
 647
 648         switch (result) {
 649         case -EINVAL:
 650                 return AE_BAD_PARAMETER;
 651                 break;
 652         case -ENODEV:
 653                 return AE_NOT_FOUND;
 654                 break;
 655         case -ETIME:
 656                 return AE_TIME;
 657                 break;
 658         default:
 659                 return AE_OK;
 660         }
 661 }
 662
 663 /* --------------------------------------------------------------------------
 664                                Driver Interface
 665    -------------------------------------------------------------------------- */
 666 static acpi_status
 667 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 668
 669 static struct acpi_ec *make_acpi_ec(void)
 670 {
 671         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 672         if (!ec)
 673                 return NULL;
 674         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 675         mutex_init(&ec->mutex);
 676         init_waitqueue_head(&ec->wait);
 677         INIT_LIST_HEAD(&ec->list);
 678         spin_lock_init(&ec->lock);
 679         return ec;
 680 }
 681
 682 static acpi_status
 683 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 684                                void *context, void **return_value)
 685 {
 686         char node_name[5];
 687         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 688         struct acpi_ec *ec = context;
 689         int value = 0;
 690         acpi_status status;
 691
 692         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 693
 694         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 695                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 696         }
 697         return AE_OK;
 698 }
 699
 700 static acpi_status
 701 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 702 {
 703         acpi_status status;
 704         unsigned long long tmp = 0;
 705
 706         struct acpi_ec *ec = context;
 707
 708         /* clear addr values, ec_parse_io_ports depend on it */
 709         ec->command_addr = ec->data_addr = 0;
 710
 711         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 712                                      ec_parse_io_ports, ec);
 713         if (ACPI_FAILURE(status))
 714                 return status;
 715
 716         /* Get GPE bit assignment (EC events). */
 717         /* TODO: Add support for _GPE returning a package */
 718         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 719         if (ACPI_FAILURE(status))
 720                 return status;
 721         ec->gpe = tmp;
 722         /* Use the global lock for all EC transactions? */
 723         tmp = 0;
 724         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 725         ec->global_lock = tmp;
 726         ec->handle = handle;
 727         return AE_CTRL_TERMINATE;
 728 }
 729
 730 static int ec_install_handlers(struct acpi_ec *ec)
 731 {
 732         acpi_status status;
 733         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 734                 return 0;
 735         status = acpi_install_gpe_handler(NULL, ec->gpe,
 736                                   ACPI_GPE_EDGE_TRIGGERED,
 737                                   &acpi_ec_gpe_handler, ec);
 738         if (ACPI_FAILURE(status))
 739                 return -ENODEV;
 740
 741         acpi_enable_gpe(NULL, ec->gpe);
 742         status = acpi_install_address_space_handler(ec->handle,
 743                                                     ACPI_ADR_SPACE_EC,
 744                                                     &acpi_ec_space_handler,
 745                                                     NULL, ec);
 746         if (ACPI_FAILURE(status)) {
 747                 if (status == AE_NOT_FOUND) {
 748                         /*
 749                          * Maybe OS fails in evaluating the _REG object.
 750                          * The AE_NOT_FOUND error will be ignored and OS
 751                          * continue to initialize EC.
 752                          */
 753                         pr_err("Fail in evaluating the _REG object"
 754                                 " of EC device. Broken bios is suspected.\n");
 755                 } else {
 756                         acpi_disable_gpe(NULL, ec->gpe);
 757                         acpi_remove_gpe_handler(NULL, ec->gpe,
 758                                 &acpi_ec_gpe_handler);
 759                         return -ENODEV;
 760                 }
 761         }
 762
 763         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 764         return 0;
 765 }
 766
 767 static void ec_remove_handlers(struct acpi_ec *ec)
 768 {
 769         acpi_disable_gpe(NULL, ec->gpe);
 770         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 771                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 772                 pr_err("failed to remove space handler\n");
 773         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 774                                 &acpi_ec_gpe_handler)))
 775                 pr_err("failed to remove gpe handler\n");
 776         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 777 }
 778
 779 static int acpi_ec_add(struct acpi_device *device)
 780 {
 781         struct acpi_ec *ec = NULL;
 782         int ret;
 783
 784         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 785         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 786
 787         /* Check for boot EC */
 788         if (boot_ec &&
 789             (boot_ec->handle == device->handle ||
 790              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 791                 ec = boot_ec;
 792                 boot_ec = NULL;
 793         } else {
 794                 ec = make_acpi_ec();
 795                 if (!ec)
 796                         return -ENOMEM;
 797         }
 798         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 799                 AE_CTRL_TERMINATE) {
 800                         kfree(ec);
 801                         return -EINVAL;
 802         }
 803
 804         /* Find and register all query methods */
 805         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 806                             acpi_ec_register_query_methods, NULL, ec, NULL);
 807
 808         if (!first_ec)
 809                 first_ec = ec;
 810         device->driver_data = ec;
 811
 812         ret = !!request_region(ec->data_addr, 1, "EC data");
 813         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 814         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 815         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 816
 817         pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 818                           ec->gpe, ec->command_addr, ec->data_addr);
 819
 820         ret = ec_install_handlers(ec);
 821
 822         /* EC is fully operational, allow queries */
 823         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 824         return ret;
 825 }
 826
 827 static int acpi_ec_remove(struct acpi_device *device)
 828 {
 829         struct acpi_ec *ec;
 830         struct acpi_ec_query_handler *handler, *tmp;
 831
 832         if (!device)
 833                 return -EINVAL;
 834
 835         ec = acpi_driver_data(device);
 836         ec_remove_handlers(ec);
 837         mutex_lock(&ec->mutex);
 838         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 839                 list_del(&handler->node);
 840                 kfree(handler);
 841         }
 842         mutex_unlock(&ec->mutex);
 843         release_region(ec->data_addr, 1);
 844         release_region(ec->command_addr, 1);
 845         device->driver_data = NULL;
 846         if (ec == first_ec)
 847                 first_ec = NULL;
 848         kfree(ec);
 849         return 0;
 850 }
 851
 852 static acpi_status
 853 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 854 {
 855         struct acpi_ec *ec = context;
 856
 857         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 858                 return AE_OK;
 859
 860         /*
 861          * The first address region returned is the data port, and
 862          * the second address region returned is the status/command
 863          * port.
 864          */
 865         if (ec->data_addr == 0)
 866                 ec->data_addr = resource->data.io.minimum;
 867         else if (ec->command_addr == 0)
 868                 ec->command_addr = resource->data.io.minimum;
 869         else
 870                 return AE_CTRL_TERMINATE;
 871
 872         return AE_OK;
 873 }
 874
 875 int __init acpi_boot_ec_enable(void)
 876 {
 877         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 878                 return 0;
 879         if (!ec_install_handlers(boot_ec)) {
 880                 first_ec = boot_ec;
 881                 return 0;
 882         }
 883         return -EFAULT;
 884 }
 885
 886 static const struct acpi_device_id ec_device_ids[] = {
 887         {"PNP0C09", 0},
 888         {"", 0},
 889 };
 890
 891 /* Some BIOS do not survive early DSDT scan, skip it */
 892 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 893 {
 894         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 895         return 0;
 896 }
 897
 898 /* ASUStek often supplies us with broken ECDT, validate it */
 899 static int ec_validate_ecdt(const struct dmi_system_id *id)
 900 {
 901         EC_FLAGS_VALIDATE_ECDT = 1;
 902         return 0;
 903 }
 904
 905 /* MSI EC needs special treatment, enable it */
 906 static int ec_flag_msi(const struct dmi_system_id *id)
 907 {
 908         pr_debug("Detected MSI hardware, enabling workarounds.\n");
 909         EC_FLAGS_MSI = 1;
 910         EC_FLAGS_VALIDATE_ECDT = 1;
 911         return 0;
 912 }
 913
 914 /*
 915  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 916  * the GPE storm threshold back to 20
 917  */
 918 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 919 {
 920         pr_debug("Setting the EC GPE storm threshold to 20\n");
 921         ec_storm_threshold  = 20;
 922         return 0;
 923 }
 924
 925 static struct dmi_system_id ec_dmi_table[] __initdata = {
 926         {
 927         ec_skip_dsdt_scan, "Compal JFL92", {
 928         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 929         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 930         {
 931         ec_flag_msi, "MSI hardware", {
 932         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 933         {
 934         ec_flag_msi, "MSI hardware", {
 935         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 936         {
 937         ec_flag_msi, "MSI hardware", {
 938         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 939         {
 940         ec_flag_msi, "MSI hardware", {
 941         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 942         {
 943         ec_flag_msi, "Quanta hardware", {
 944         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 945         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 946         {
 947         ec_flag_msi, "Quanta hardware", {
 948         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 949         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 950         {
 951         ec_validate_ecdt, "ASUS hardware", {
 952         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 953         {
 954         ec_validate_ecdt, "ASUS hardware", {
 955         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 956         {
 957         ec_enlarge_storm_threshold, "CLEVO hardware", {
 958         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 959         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 960         {
 961         ec_skip_dsdt_scan, "HP Folio 13", {
 962         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 963         DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL},
 964         {
 965         ec_validate_ecdt, "ASUS hardware", {
 966         DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
 967         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
 968         {},
 969 };
 970
 971 int __init acpi_ec_ecdt_probe(void)
 972 {
 973         acpi_status status;
 974         struct acpi_ec *saved_ec = NULL;
 975         struct acpi_table_ecdt *ecdt_ptr;
 976
 977         boot_ec = make_acpi_ec();
 978         if (!boot_ec)
 979                 return -ENOMEM;
 980         /*
 981          * Generate a boot ec context
 982          */
 983         dmi_check_system(ec_dmi_table);
 984         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 985                                 (struct acpi_table_header **)&ecdt_ptr);
 986         if (ACPI_SUCCESS(status)) {
 987                 pr_info("EC description table is found, configuring boot EC\n");
 988                 boot_ec->command_addr = ecdt_ptr->control.address;
 989                 boot_ec->data_addr = ecdt_ptr->data.address;
 990                 boot_ec->gpe = ecdt_ptr->gpe;
 991                 boot_ec->handle = ACPI_ROOT_OBJECT;
 992                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 993                 /* Don't trust ECDT, which comes from ASUSTek */
 994                 if (!EC_FLAGS_VALIDATE_ECDT)
 995                         goto install;
 996                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 997                 if (!saved_ec)
 998                         return -ENOMEM;
 999         /* fall through */
1000         }
1001
1002         if (EC_FLAGS_SKIP_DSDT_SCAN)
1003                 return -ENODEV;
1004
1005         /* This workaround is needed only on some broken machines,
1006          * which require early EC, but fail to provide ECDT */
1007         pr_debug("Look up EC in DSDT\n");
1008         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1009                                         boot_ec, NULL);
1010         /* Check that acpi_get_devices actually find something */
1011         if (ACPI_FAILURE(status) || !boot_ec->handle)
1012                 goto error;
1013         if (saved_ec) {
1014                 /* try to find good ECDT from ASUSTek */
1015                 if (saved_ec->command_addr != boot_ec->command_addr ||
1016                     saved_ec->data_addr != boot_ec->data_addr ||
1017                     saved_ec->gpe != boot_ec->gpe ||
1018                     saved_ec->handle != boot_ec->handle)
1019                         pr_info("ASUSTek keeps feeding us with broken "
1020                         "ECDT tables, which are very hard to workaround. "
1021                         "Trying to use DSDT EC info instead. Please send "
1022                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1023                 kfree(saved_ec);
1024                 saved_ec = NULL;
1025         } else {
1026                 /* We really need to limit this workaround, the only ASUS,
1027                 * which needs it, has fake EC._INI method, so use it as flag.
1028                 * Keep boot_ec struct as it will be needed soon.
1029                 */
1030                 if (!dmi_name_in_vendors("ASUS") ||
1031                     !acpi_has_method(boot_ec->handle, "_INI"))
1032                         return -ENODEV;
1033         }
1034 install:
1035         if (!ec_install_handlers(boot_ec)) {
1036                 first_ec = boot_ec;
1037                 return 0;
1038         }
1039 error:
1040         kfree(boot_ec);
1041         boot_ec = NULL;
1042         return -ENODEV;
1043 }
1044
1045 static struct acpi_driver acpi_ec_driver = {
1046         .name = "ec",
1047         .class = ACPI_EC_CLASS,
1048         .ids = ec_device_ids,
1049         .ops = {
1050                 .add = acpi_ec_add,
1051                 .remove = acpi_ec_remove,
1052                 },
1053 };
1054
1055 int __init acpi_ec_init(void)
1056 {
1057         int result = 0;
1058
1059         /* Now register the driver for the EC */
1060         result = acpi_bus_register_driver(&acpi_ec_driver);
1061         if (result < 0)
1062                 return -ENODEV;
1063
1064         return result;
1065 }
1066
1067 /* EC driver currently not unloadable */
1068 #if 0
1069 static void __exit acpi_ec_exit(void)
1070 {
1071
1072         acpi_bus_unregister_driver(&acpi_ec_driver);
1073         return;
1074 }
1075 #endif  /* 0 */